Tachykinins, which form a group of peptidergic neurotransmitters, play an important role in nociception functioning as a biowarning system, as well as the emotion cycle. Desctruction of such a biowarning system readily causes a variety of diseases and disorders inculuding irritable bowel syndrome (IBS), pain, anxiety, obstructive bronchial diseases, headache, and vomiting. In mammals, substance P, neurokinin A, and neurokinin B are known tachykinins, and these tachykinin species have high affinity with respect to NK-1 receptor, NK-2 receptor, and NK-3 receptor, respectively.
Tachykinin receptor antagonists have been used as drugs for treating various diseases caused by destruction of the biowarning system. For example, the following compounds (A), (B) and (C) are low-molecular weight non-peptidergic compounds known to exhibit antagonistic activity against both NK-1 receptor and NK-2 receptor (Patent Documents 1 to 3).


However, actually, compound (B) in vitro exhibits antagonistic activity only to NK-2 receptor. When any of compounds (A) to (C) are perorally administered, satisfactory antagonistic activity is not always attained (Patent Documents 2 and 4).
Meanwhile, the aforementioned optically active sulfoxide derivative (D) is known to exhibit excellent antagonistic activity against both NK-1 receptor and NK-2 receptor (see Patent Document 4). However, there are only a limited number of reports on low-molecular-weight compounds exhibiting antagonistic activity against NK-1 receptor or NK-2 receptor.
Patent Document 1: International Patent Publication WO94/29309 pamphlet)
Patent Document 2: International Patent Publication WO94/17045 pamphlet)
Patent Document 3: International Patent Publication WO94/26735 pamphlet)
Patent Document 4: Japanese Patent Application Laid-Open (kokai) No. 11-43490